There was a companion who had to travel through a valley. Suddenly a thief stopped him and put a sword to his neck. He told him “I am going to kill you and take your merchandise”. The man said “You can take me merchandise but please let me live” The thief said no.
The man asked him to do one last thing before he died, so he prayed two rakat prayer. During sujood he asked Allah, by his wonderful names, begged Allah to save him from this thief. He recited 3 times “Oh the one who saves, saves me”. Then he hears the galloping of a horse and the man on it comes and kills that thief. The man asked him “Who are you”, he responded that he is an angel, Allah responded to his duas he made while in sujood.